Absorbent article and method for manufacturing an absorbent article

ABSTRACT

An absorbent article comprises an absorbent core sandwiched between a topsheet and a backsheet. The article defines a front portion, a back portion and a crotch portion. The absorbent core comprises an absorbent component enclosed by a core cover comprising an upper and a lower side, and the core is formed with a sealing arrangement for joining the upper and lower sides comprising two channel sealings extending along an longitudinal axis in the crotch portion and defining a first channel sealing width and a second channel sealing width, respectively. The front portion of the core is formed with a recess defining a depth extending from a front edge of the core and into the front portion. A distance is defined between said front edge of the core and a front edge of each channel sealing, such that the ratio of the depth and the distance is within the interval 0.05-0.8.

TECHNICAL FIELD

The disclosure relates to an absorbent article comprising an absorbentcore sandwiched between a liquid-permeable topsheet and aliquid-impermeable backsheet.

The disclosure also relates to an absorbent core for an absorbentarticle, and a method for manufacturing an absorbent article of theabove-mentioned type.

BACKGROUND

Wearable and disposable absorbent articles, for example in the form ofdiapers, incontinence garments, feminine garments and the like, are wellknown. Such articles are used to absorb, distribute and store bodyexudates while providing a high level of comfort and sense of dryness tothe wearer during use.

A conventional disposable absorbent article in the form of a diaper isnormally designed with an absorbent core which is sandwiched between atopsheet and a backsheet. The article is arranged along a longitudinalaxis and along a transversal axis which extends in a perpendiculardirection in relation to the longitudinal axis. Furthermore, the articlecan be divided into a front portion, a back portion and a crotchportion, and the core being positioned in the crotch portion.

The area around the navel of the user is of particular importance whenthe absorbent article is used by newborn and very young children.

DE 29513199 discloses a disposable diaper having an absorbent corewhich, according to an embodiment, is formed with a cut out portionwhich is positioned close to an area where the navel of a user islocated when wearing the article.

SUMMARY

The present disclosure is based on the insight that the overall comfortand fit of a diaper can be optimized by arranging a recess in anabsorbent core in a particular manner.

In accordance with the disclosure there is provided an absorbentarticle, a core and a method for manufacturing an absorbent article.

The absorbent article comprises an absorbent core sandwiched between atopsheet and a backsheet, said article being arranged along alongitudinal axis and a transversal axis extending in a perpendiculardirection in relation to the longitudinal axis and said article defininga front portion, a back portion and a crotch portion, wherein saidabsorbent core comprises an absorbent component enclosed by a core covercomprising an upper and a lower side and the core is formed with asealing arrangement for joining said upper and lower sides comprisingtwo channel sealings extending along said longitudinal axis in saidcrotch portion and defining a first channel sealing width and a secondchannel sealing width, respectively. Furthermore, the front portion ofthe core is formed with a recess defining a depth extending from a frontedge of the core and into said front portion and that a distance isdefined between said front edge of the core and a front edge of eachchannel sealing, wherein the ratio of said depth and said distance iswithin the interval 0.05-0.8, such as 0.15-0.4.

The disclosure fulfills requirements on an absorbent article related toimproved fit, comfort and function. There is provided an absorbentarticle in which the absorbent core, in particular, in its front portionis formed with a recess which is arranged in a manner so that a correctpositioning of the absorbent article can be obtained, in particular inrelation to the area where the navel of the user is located and at thesame time in relation to the crotch portion of the user.

The disclosure is particularly relevant in absorbent articles fornewborn babies and very young children, where the need for care of thenavel and the area around the navel is particularly important whilekeeping the diaper in place in the crotch portion.

Also, due to that the absorbent article comprises the above-mentionedtwo channel sealings, it may be an advantage to arrange the article sothat the fluid which is released into the absorbent core can contributeto a sufficiently stiff crotch portion of the core (in the wet conditionof the article), to reduce the risk for sagging of the crotch portion ofthe article during use.

The recess may be formed in the absorbent component. Also, the recessmay be formed in the core cover and the absorbent component.

Furthermore, the distance between the channel sealings in a transversaldirection of the article may be less than the maximum width of saidrecess. The width of the recess may be between 30-70 mm, such as 40-60mm.

The recess may be shaped generally as a semi-circle, a U-shape, aV-shape or in the form of a rectangle extending into the front portion.

The distance between said front edge of the core and the front edge ofeach channel sealing may be within the interval 50-180 mm, such as75-110 mm.

The depth of the recess may be within the interval 10-40 mm, such as15-30 mm.

The core may comprise at least one wetness indicator having alongitudinal extension and being positioned generally only in said frontportion, or only in said back portion, or in both the front portion andthe back portion.

The wetness indicator may be a change indicator.

The wetness indicator may be arranged so that it does not extend intosaid crotch portion. Also, the wetness indicator may be arranged so thatit does not extend between said channel sealings.

The wetness indicator may be located along said longitudinal axis.

The wetness indicator may be located between said backsheet and saidcore cover, such as between the backsheet and the lower core cover side.

The absorbent article may be in the form of an open diaper or a pantstype diaper.

The channel sealings may be formed by a thermo- and/or mechanicalwelding pattern.

The welding pattern may comprise a plurality of welding spots arrangedin the form of a first row in which the welding spots extend along afirst axis and a second row in which the welding spots extend along asecond axis, said first axis and second axis defining a first angle inrelation to each other. The first angle may be 45-130°, such as 45-100°,such as 45-70°.

The welding spots may be generally rectangular or oblong.

The first axis may define a second angle with reference to saidlongitudinal axis which is within the interval 30-60°.

The channel sealings may be positioned within two corresponding channelswhich constitute sections of the absorbent core which are generally freefrom absorbent material.

The article may comprise two side seams along the sides of said core.

The article may be arranged with a centre segment having a first widthand being defined in the absorbent component between the channelsealings and two side segments each having a second width and beingdefined in the absorbent component outside each channel sealing.

The absorbent component may be formed so that the total amount ofabsorbent material in the centre segment is generally equal to, orgreater than, the total amount of absorbent material in each one of theside segments.

A third width may be defined between the channel sealings and a fourthwidth may be defined between a channel sealing and a side seam, and theratio of the first width and the third width may be greater than theratio of the second width and the fourth width.

The absorbent article may be configured so that 33-41% by weight of thetotal amount of absorbent material in the crotch portion is in thecentre segment and 25-33% by weight of the total absorbent material inthe crotch portion is in each one of the side segments.

The absorbent material in said crotch portion may comprise pulp materialand superabsorbent material, said pulp material having a basis weightwhich is in the interval of 50-400 g/m² and said superabsorbent materialhaving a basis weight which is in the interval of 100-900 g/m².

The ratio of the first width and the third width may be in the interval0.75-0.91, such as 0.80-0.86 and the ratio of the second width and thefourth width may in the interval 0.57-0.71, such as 0.62-0.66.

The first, second, third and fourth widths may be configured so thatb1<b2*2 and a1<a2*2.

The absorbent component comprises absorbent material with a basis weightwhich may be within the interval 400-700 g/m² and having a maximumdeviation of ±5% of said basis weight.

The channel sealings may be generally straight. Also, the channelsealings may be generally parallel to said longitudinal axis. Theabsorbent core may be generally rectangular.

There is also provided an absorbent core for an absorbent article, saidabsorbent core comprising an absorbent component enclosed by a corecover comprising an upper and lower side and a sealing arrangement forjoining said upper and lower sides, said sealing arrangement comprisingtwo channel sealings extending along said longitudinal axis in saidcrotch portion and defining a first channel sealing width and a secondchannel sealing width, respectively. Furthermore, the core comprises afront portion which is formed with a recess defining a depth extendingfrom a front edge of the core and into said front portion and that adistance is defined between said front edge of the core and a front edgeof each channel sealing, wherein the ratio of said depth and saiddistance is within the interval 0.05-0.8, such as 0.15-0.4.

There is also provided a method for manufacturing an absorbent article,the article comprising a longitudinal axis and a transversal axisextending in a perpendicular direction in relation to the longitudinalaxis and said article defining a front portion, a back portion and acrotch portion, comprising: forming an absorbent core with an absorbentcomponent and enclosing said absorbent component in a core covercomprising an upper and a lower side; providing two channel sealings inthe crotch portion joining said upper and lower core cover sides; andsandwiching said absorbent core between a liquid-permeable topsheet anda liquid-impermeable backsheet. Furthermore, the forming stepfurthermore comprises: forming a recess in a front portion of the core,said recess defining a depth extending from a front edge of the core andinto said front portion; and forming the core so that a distance isdefined between said front edge of the core and a front edge of eachchannel sealing, wherein the ratio of said depth and said distance iswithin the interval 0.05-0.8, such as 0.15-0.4.

Further advantages and advantageous features of the disclosure aredisclosed in the following description.

BRIEF DESCRIPTION OF THE DRAWINGS

The disclosure will be described in greater detail below with referenceto the figures shown in the appended drawings, wherein

FIG. 1 shows a view from above of an absorbent article in the form of adiaper;

FIG. 2 shows a cross-sectional view of the diaper;

FIG. 3 shows a view from above of an absorbent core intended to be usedin said diaper shown in FIGS. 1 and 2;

FIG. 4 shows a welding pattern; and

FIG. 5 shows a further view of a welding pattern.

DETAILED DESCRIPTION

Different aspects of the present disclosure will be described more fullyhereinafter with reference to the enclosed drawings. The embodimentsdisclosed herein can, however, be realized in many different forms andshould not be construed as being limited to the aspects set forthherein.

With initial reference to FIG. 1, there is shown a view from above of anabsorbent article 1 in the form of a baby diaper. The absorbent article1 is shown in FIG. 1 in an unfolded and flat state. Also, the absorbentarticle 1 is based on an absorbent structure for absorbing body exudatesfrom a wearer to provide a dry and comfortable fit for the wearer.

As shown in FIG. 1, the absorbent article 1 comprises a liquid-permeabletopsheet 3, a liquid-impermeable backsheet 4 an absorbent core 5 whichis sandwiched between the topsheet 3 and the backsheet 4. The topsheet 3is arranged at the surface of the article 1, i.e., at the side which isfacing the wearer, whereas the backsheet 4 is arranged at the undersideof the article 1. Furthermore, both the topsheet 3 and the backsheet 4may extend laterally outside of the absorbent core 5 along the entireperimeter of the article 1.

The absorbent core shown in FIG. 1 has a rectangular design. However,the disclosure is not limited to this design but may be formed ingenerally any geometric form within the scope of the disclosure.

The topsheet 3, backsheet 4 and the absorbent core 5 may consist of anymaterials suitable for their purposes, as will be discussed in furtherdetail below.

As shown in FIG. 1, the absorbent article 1 has a longitudinal extensionalong a longitudinal axis y1 and a transverse extension along atransverse axis x1, which is perpendicular to the longitudinal axis y1.Furthermore, the absorbent article 1 may be defined as being dividedinto a front portion 6, a back portion 7 and a crotch portion 8. Thefront 6 and back portions each having a waist edge 2. The front portion6 is intended to be oriented in a direction towards the wearer's bellyduring use of the article 1.

Furthermore, with reference to FIGS. 1 and 2, wherein FIG. 2 is across-sectional view of the absorbent article 1 along the transversalaxis x1, it should be noted that the absorbent core 5 comprises anabsorbent component 5 a, 5 b, 5 c which is sandwiched between an uppercore cover side 11 and a lower core cover side 12, and is formed withtwo longitudinally extending and generally straight channel sealings 9,10 which are configured so as to join the upper core cover side 11 tothe lower core cover side 12, see in particular FIG. 2, wherein theabsorbent core 5 is sandwiched between said upper core cover side 11 andsaid lower core cover side 12. The disclosure is not limited to a corecover comprising two core cover layers. The core cover may be of onesingle material layer. The absorbent component may be enclosed by onecore cover layer folded in two, or enclosed by a continuous core coversheet, thereby providing upper and lower core cover sides for enclosingthe absorbent component.

The upper core cover side 11 and the lower core cover side 12 may beattached to each other by various technologies, for example, by thermo-and/or mechanical bonding, such as thermo-sealing, ultrasonic bonding,and may be in combination with an adhesive or adhesives or stitching orthe like. According to FIGS. 1 and 2, the upper core cover side 11 andthe lower core cover side 12 are attached to each other by ultrasonicwelding.

The channel sealings 9, 10 are positioned along two correspondingchannels 13, 14 which constitute sections of the absorbent core 5 whichare not filled with absorbent material. This may be obtained throughmanufacturing the absorbent core 5 involving a mat forming processduring which absorbent material is omitted from the areas whichcorrespond to the channels 13, 14. In this manner, no absorbent materialwill be present in the channels 13, 14, i.e., where the channel sealings9, 10 are arranged.

As shown in FIG. 1, the front portion 6 of the core 5 is formed with arecess 27. This recess 27 will be described in greater detail below withreference primarily to FIG. 4.

As shown in FIGS. 1 and 2, the absorbent core 5 may be divided into acentre segment 5 a and two side segments 5 b, 5 c in the crotch portion8. The two above-mentioned channels 13, 14, and the channel sealings 9,10 will consequently be configured so that they separate the threesegments 5 a, 5 b, 5 c from each other along the crotch area 8. Also,the length l1′ of each channel sealing 9, 10 (see FIG. 3) may correspondto the length l1 of the crotch portion 8 and may also be slightly lessthan the length of each channel 13, 14.

The absorbent core 5 may be generally rectangular and comprise twogenerally straight channel sealings 9, 10 which are generally parallelto said longitudinal axis y1 and define a first channel sealing width w1and a second channel sealing width w2. The disclosure is not limited toa rectangular core 5 and generally straight channel sealings 9, 10,i.e., other geometrical configurations may occur. The channel sealings9, 10 are positioned within the first channel 13 and the second channel14, respectively, and are configured to attach the upper core cover side11 to the lower core cover side 12.

Furthermore, the centre segment 5 a may be defined in the core 5 betweenthe channel sealings 9, 10. Also, the two side segments 5 b, 5 c may bedefined in the core 5 outside each channel sealing 9, 10. Moreprecisely, the first side segment 5 b is positioned between the firstchannel sealing 9 and a first side seam 15, whereas the second sidesegment 5 c is positioned between the second channel sealing 10 and asecond side seam 16. The side seams 15, 16 are configured for joiningthe upper core cover 11 to the lower core cover 12, suitably by means ofultrasonic welding or other relevant technologies as described abovewith reference to the channel sealings 9, 10. Furthermore, the sideseams 15, 16 extend along each side of the absorbent core 5, along afirst side edge 17 and a second side edge 18 of the absorbent core 5.

As mentioned, the length l1 of the crotch portion 8 may equal the lengthof the channel sealings 9, 10, i.e., the channel sealings 9, 10 mayextend along the crotch portion 8 only. However, the side seams 15, 16may not just be positioned along the crotch portion 8 but also extendalong the front portion 6 and the back portion 7. This will be describedin detail below.

In summary, the absorbent core 5 is formed with a sealing arrangementwhich is constituted by the two channel sealings 9, 10 and optionallyalso the two side seams 15, 16. The sealing arrangement may beconfigured so that, in the crotch portion 8, the absorbent core 5 isdivided into a centre segment 5 a and two side segments 5 b, 5 c. Moreprecisely, and as shown in FIG. 2, the centre segment 5 a has a firstwidth a1 and each side segment 5 b, 5 c has a second width a2. Also, athird width b1 is defined between the two channel sealings 9, 10.Furthermore, a fourth width b2 is defined between the first channelsealing 9 and the first side seam 15, and also between the secondchannel sealing 10 and the second side seam 16.

According to FIGS. 1 and 2, the absorbent component 5 a, 5 b 5 c may beconfigured so that the total amount of absorbent material of the centresegment 5 a is generally equal to or greater than the total amount ofabsorbent material in each one of the side segments 5 b, 5 c. As will bedescribed in greater detail below, the absorbent material may comprise amixture of pulp material and superabsorbent material. Also, the ratio ofthe first width a1 and the third width b1 is greater than the ratio ofthe second width a2 and the fourth width b2. In practical terms, thismeans that the available space for expansion of the absorbent materialin the centre segment 5 a, during use of the absorbent article 1 in itswet condition, is less than the corresponding available space for eachside segment 5 b, 5 c. This will lead to a situation in which the centresegment 5 a will be stiffer (in its wet condition) than the sidesegments 5 b, 5 c. This means that any tendency in the crotch portion 8of the absorbent article 1 to sag will be reduced, in particular in itswet condition.

The expression “generally equal” as used above for describing the amountof absorbent material in the centre segment 5 a as compared with theside segments 5 b, 5 c should be interpreted in a manner wherein theamount of absorbent material could have a variation of approximately ±5%in any part of the crotch portion 8.

The absorbent article 1 may be configured so that 33-41% by weight ofthe total amount of absorbent material in the crotch portion 8 is l inthe centre segment 5 a, whereas 25-33% by weight of the total absorbentmaterial in the crotch portion 8 is in each one of the side segments 5b, 5 c. In this manner, the desired stiffness in the centre segment 5 amay be obtained.

In summary, the absorbent core 5 may comprise an absorbent componentwhich in turn comprises the three above-mentioned segments 5 a, 5 b, 5 cin the crotch portion 8 of the absorbent article 1. In the crotchportion 8, the absorbent component 5 a, 5 b, 5 c comprises absorbentmaterial which may be in the form of pulp material and superabsorbentmaterial. The pulp material may have a basis weight which is in theinterval of 50-400 g/m² and the superabsorbent material may have a basisweight which is in the interval of 100-900 g/m². However, a deviation of±5% of the chosen basis weight in the crotch portion 8 is accepted toobtain the purpose of providing a sufficiently stiff centre segment 5 aand a reduction of the tendency for the article 1 to sag, as describedabove.

Various types of materials may be used for the absorbent article 1. Thetopsheet 3 is arranged to face the wearer of the absorbent article 1when worn. The topsheet 3 may be formed by a fluid permeable nonwovenfabric or film which is made of thermoplastic synthetic fibers. Thetopsheet 3 may be sufficiently liquid-permeable to allow discharged bodyfluids to penetrate through the thickness of the topsheet 3. Also, thetopsheet 3 may be suitably manufactured from a material which iscompliant and soft-feeling to the skin of the wearer. The topsheet 3 mayconsist of a single layer or have a laminate structure comprising aplurality of layers, for example, two or more layers. The layers may bemade of the same material, or some or all the layers may be made ofdifferent materials.

The layer of the topsheet 3 or, for the case of a laminate structure,one, some, or all layers of the topsheet may be made of a singlematerial or have plural portions made of different materials, e.g.,within different parts of the wearer-facing surface of the topsheet.

The layer of the topsheet 3 or, for the case of a laminate structure,one, some or all layers of the topsheet may be a nonwoven material, aperforated plastic film, a plastic or textile mesh, or a liquidpermeable foam layer.

The layer of the topsheet 3 or, for the case of a laminate structure,one, some or all of the layers of the topsheet may be, for example, ahydrophilic, non-apertured nonwoven web of fibers, such as naturalfibers, e.g., cotton or pulp fibers, synthetic fibers, e.g., polyesteror polypropylene fibers, or a combination of these fibers.

The topsheet may have a basis weight in the range of 8-40 g/m². However,the disclosure is not limited to topsheets having this basis weightonly.

Furthermore, the backsheet 4 may be constituted by a liquid-impermeableand breathable layer such as a polymeric film, for example a film ofpolyethylene or polypropylene. According to different embodiments, thematerials which may be used for the backsheet 4 include thin andflexible fluid impermeable plastic films, or fluid impermeable nonwovenmaterials, fluid impermeable foams and fluid impermeable laminates.

The backsheet 4 may be formed by a single layer, but may alternativelybe formed by a multi-layered structure, i.e., a laminate, wherein atleast one layer is fluid impermeable. Furthermore, the backsheet 4 maybe elastic in any direction.

Furthermore, the backsheet 4 may have a laminate structure comprising aliquid barrier sheet and a nonwoven layer arranged on top of each other(not shown in detail in the drawings), wherein the nonwoven layer isarranged at an outer side away from the wearer of the absorbent article1 when worn.

The nonwoven layer may be made of thermoplastic polymer material fibersor filaments. The nonwoven layer may be formed by a variety of differentprocesses, such as spunbonding, airlaying, meltblowing or bonded cardedweb formation processes. The nonwoven layer may be made of an SMS(spunbond/meltblown/spunbond) or SS (spunbond/spunbond) nonwovenmaterial of polypropylene or bicomponent fibers of polypropylene andpolyethylene, or of a combination of such materials. The nonwoven layermay have a basis weight in the range of 5-40 g/m².

The liquid barrier sheet may be made of a plastic material, for examplea thermoplastic film material, and/or a nonwoven material. For example,the liquid barrier sheet may be formed as a plastic layer, e.g., athermoplastic layer, or a plastic film, e.g., a thermoplastic film.Forming the liquid barrier sheet of a plastic material, such as athermoplastic film material, allows for a particularly good printabilityof the liquid barrier sheet. The liquid barrier sheet may also containpaper fibers.

The liquid barrier sheet may be a liquid impermeable, breathable ornon-breathable layer. The liquid barrier sheet may consist of a singlelayer or have a laminate structure with a plurality of layers, e.g., twoor more layers, three or more layers, or four or more layers. The layersof the liquid barrier sheet may be laminated, bonded or attached to eachother, for example, by thermo- and/or mechanical bonding, such asthermo-sealing, ultrasonic bonding, such as ultrasonic welding, anadhesive or adhesives, stitching or the like.

The liquid barrier sheet may be a breathable microporous film. Themicroporous film may be made of a material comprising at least two basiccomponents, namely a thermoplastic elastomeric polyolefin polymer and afiller. These components and, in some embodiments, additional othercomponents may be mixed together, heated and subsequently extruded intoa mono-layer or multi-layer film using any one of various film-producingprocesses, such as cast embossed, chill and flat cast, and blown filmprocesses.

Regarding the choice of materials for the various layers in theabsorbent article, the materials may be chosen for the bonding processto form the channel sealings and side seams. For example, if ultrasonicwelding is chosen for joining the upper and lower core cover layers, thechosen materials for the core cover may be adapted to form a secure bondduring ultrasonic welding.

Furthermore, the absorbent core 5 is provided between the topsheet 3 andthe backsheet 4 to absorb the liquid, such as urine or other bodilyfluids, which has passed through the topsheet 3. The absorbent core 5may be made of one layer only, made from any suitable absorbent orliquid uptake material, such as one or more layers of cellulose fluffpulp, foam, fiber waddings or the like.

The absorbent core 5 may comprise suitable amounts of superabsorbentparticles. Such superabsorbent material is well known in the field ofabsorbent articles, and is constituted by a water-swellable andwater-insoluble material which is capable of absorbing large quantitiesof fluid upon formation of a hydrogel. The absorbent core 5 may containsuperabsorbent material in the form of fibers or particles of absorbentpolymer material. For example, the superabsorbent material may besurface cross-linked, partially neutralized polyacrylates.

Furthermore, the core cover 11, 12 as mentioned above may be made ofnonwoven material, with a basis weight of 5-20 g/m². The nonwovenmaterial may be of thermoplastic polymer fibers or filaments. Thenonwoven may be formed by a variety of different processes such asspunbonding, airlaying, meltblowing or bonded carded web formationprocesses. The core cover may be of an SMS (spunbond/meltblown/spunbond)or SS (spunbond/spunbond) nonwoven material and may be of polypropyleneor bicomponent fibers of polypropylene and polyethylene, or of acombination of the same.

The superabsorbent material, e.g., the superabsorbent fibers orparticles, may be mixed with other absorbent or liquid uptake materialor materials, such as cellulose fluff pulp, and/or arranged in pocketsor layers in the absorbent core 5. The ratio of superabsorbent materialand pulp in the absorbent core 5 may be 0-50% by weight pulp fibers and50-100% by weight superabsorbent material.

The absorbent core 5 may further comprise components for improving theproperties of the absorbent core 5. For example, the absorbent core 5may comprise a binder or binders, such as binder fibers.

Furthermore, as known by the skilled person, the various layers of theabsorbent article 1 may be attached by means of adhesive material. Suchadhesive is not shown in the drawings.

One or more additional layers may be provided in the absorbent article1. For example, an acquisition layer may be arranged between theabsorbent core 5 and the topsheet 3. Such an additional layer may forexample be in the form of an airlaid layer, a spunlace layer, ahigh-loft, foam or any other type of material layer which may be used inan absorbent article to act as a liquid acquisition and absorptionlayer. The acquisition layer is adapted to quickly receive andtemporarily store discharged liquid before it is absorbed by theabsorbent core. Such acquisition layer may be composed of for exampleairlaid nonwoven, spunlace nonwoven, high loft nonwoven or foammaterials. An airlaid nonwoven may be produced with fluff, wood pulp,and here the fluff fibres are dispersed into a fast-moving air streamand condensed onto a moving screen by means of pressure and vacuum.

According to an embodiment, the ratio of the first width a1 of thecentre segment 5 a and the third width b1, i.e., the distance betweenthe channel sealings 9, 10 (i.e., a1/b1) may be in the interval0.75-0.91, such as 0.80-0.86. Furthermore, the ratio of the second widtha2 of each side segment 5 b, 5 c and the fourth width b2, i.e., thedistance between each channel sealing 9, 10 and its corresponding,adjacent side seam 11, 12 (i.e., a2/b2) may be in the interval0.57-0.71, such as 0.62-0.66. In this manner, the required stiffness ofthe centre segment 5 a may be obtained.

In general, the article 1 may be arranged so that the ratio of the firstwidth a1 and the third width b1 is greater than the ratio of the secondwidth a2 and the fourth width b2, i.e.,(a1/b1)>(a2/b2)Furthermore, the first, second, third and fourth widths a1, a2, b1, b2,respectively, may be configured so that:b1<b2*2 and a1<a2*2

In addition to the arrangement of the first, second, third and fourthwidths a1, a2, b1, b2, as described above, the absorbent article 1 maybe arranged to provide the desired stiffness of the centre segment 5 aand the entire absorbent article 1 by the above-mentioned arrangement ofthe absorbent material in the absorbent core 5. This means that thecentre segment 5 a may be configured for a stiffness in a wet conditionwhich is greater than that of each side segment 5 b, 5 c. This alsomeans that the absorbent component, i.e., consisting of the centresegment 5 a and the side segments 5 b, 5 c, may be configured with anability to expand on wetting and to display a first volume in drycondition and a second volume in completely expanded wet condition, thesecond volume being greater than the first volume.

With reference again to FIGS. 1 and 3, it can be noted that each channelsealing 9, 10 may have a length l1′ of which corresponds to thelongitudinal extension l1 of the crotch portion 8 or slightly less. Eachone of the channel sealings 9, 10 may have a length l1′ which is between5-50%, such as 10-50%, such as 28-38%, of the total length l of theabsorbent article 1. Furthermore, each channel sealing 9, 10 may have alength l1′ which is between 10-60%, such as between 20-60%, such asbetween 30-50%, of the length of the absorbent core 5.

A further parameter is the positioning of the channel sealings 9, 10along the absorbent article 1 in its longitudinal direction. Suchpositioning may be defined by choosing a suitable value for the distancel2 between the front edge 19 of the article 1 and the front edge 20 ofeach channel sealing 9, 10. Obviously, this means that decreasing saiddistance l2 means that the distance l3 between the back edge 21 of thearticle 1 and the back edge 22 of the channel sealings 9, 10 will beincreased, and vice versa.

The position of the channel sealings 9, 10 along the longitudinaldirection of the absorbent article 1 may be chosen in a manner so thatthe distance l2 between the front edge 17 of the article 1 and the frontedge 18 of each channel 9, 10 is between 15-40%, such as between 22-25%,of the total length l of the article 1.

As mentioned above, the absorbent core 5 is enclosed between an uppercore cover side 11 and a lower core cover side 12. The absorbent core 5may be manufactured as a single layer which is wrapped in nonwovenmaterial and positioned between the topsheet 3 and the backsheet 4during manufacturing of the absorbent article 1.

Furthermore, the absorbent core 5 may comprise at least one additivematerial such as a skin care composition. It may be an advantage if theside segments 5 b, 5 c comprise at least one additive material in theform of a skin care composition. This is due to the side segments 5 b, 5c normally will be closest to the body of the wearer of the absorbentarticle 1. The additive may be located on the parts of the topsheetcovering the side segments 5 b, 5 c.

According to what is known to the skilled person, the absorbent article1 may additionally be provided with further components such as fasteningtabs, elastic elements and other components which are commonly used inabsorbent articles such as for example baby diapers or incontinencegarments. Such additional components are not described in detail here.

With reference to FIG. 1, the absorbent core 5 is provided with asealing arrangement 9, 10, 15, 16, i.e., comprising the above-mentionedchannel sealings 9, 10 and optionally also the side seams 15, 16. Asshown in FIG. 1, the side seams 15, 16 may extend along the side edges17, 18 of the core.

The side seams 15,16 may define a first side seam width and a secondside seam width w4, respectively, along the crotch portion 8 of theabsorbent article 1.

As shown in FIG. 1, the channel sealings 9, 10 may be generally straightand generally parallel to the longitudinal axis x1. Also, the side seams15, 16 may be generally straight and generally parallel to thelongitudinal axis x1.

Referring now to FIG. 3, the above-mentioned recess 27 will now bedescribed in greater detail. The recess 27 defines a depth c whichextends from a front edge 28 of the core 5 and a predetermined distanceinto the front portion 6. Furthermore, a distance l2′ is defined betweenthe front edge 28 of the core 5 and a front edge 20 of each channelsealing 9, 10. The ratio of said depth c and said distance l2 ′ iswithin the interval 0.05-0.8, such as 0.15-0.4.

The recess 27 may be formed in the absorbent component 5 a, 5 b, 5 conly. Furthermore, the recess 27 may be formed in the core cover 11, 12and the absorbent component 5 a, 5 b, 5 c.

With further reference to FIG. 3, the distance b1 between the channelsealings 9, 10 in a transversal direction of the article 1 may be lessthan the maximum width b3 of said recess 27. Such an arrangement isadvantageous due to the crotch portion 8 of the article 1 can be given arelatively high stiffness when the article 1 is in its wet conditioneven with relatively low levels of released fluid. This is advantageousfor absorbent articles used by newborn babies or very young children,wherein there is less fluid released into the article as compared witholder children or adults.

The distance l2 ′ between the front edge 28 of the core 5 and the frontedge 20 of each channel sealing 9, 10 may be within the interval 50-180mm, such as 75-110 mm. Also, the depth c of the recess 27 may be withinthe interval 10-40 mm, such as 15-30 mm. Such measurements contribute tothe above-mentioned advantages provided through this disclosure.

Furthermore, the recess 27 may be shaped generally as a semi-circle, asshown in FIG. 3. The recess 27 may have a U-shape, a V-shape or the formof a rectangle extending into the front portion.

As shown in FIG. 3, the absorbent core 5 may optionally comprise awetness indicator 29, which is formed with a longitudinal extension andis positioned generally only in said front portion 6. The core 5 mayalso be provided with a wetness indicator 30 which is positioned only inthe back portion, as also shown in FIG. 3. Alternatively, the core 5 maybe provided with both wetness indicators 29, 30 as shown in FIG. 3.

The wetness indicator 29, 30 may be constituted by a relatively thinlayer of an adhesive composition comprising a colorant such as apH-indicator or a water-soluble dye as known to the skilled man in theart. One such wetness indicator is Kmelt W 2488 OL from Colquimica S.A.The wetness indicator may be sensitive to moisture and/or pH changes andchanges appearance/color when it is wet. In this manner, the wetnessindicator 29, 30 may be configured for providing a visual signal when incontact with urine. The wetness indicator may be applied by slotcoating.

The wetness indicator 29, 30 may be arranged so that it does not extendinto said crotch portion 8. Also, the wetness indicator 29, 30 may bearranged so that it does not extend between said channel sealings 9, 10.

Furthermore, the wetness indicator 29, 30 may be located along saidlongitudinal axis y1. The wetness indicator 29, 30 may be locatedbetween the backsheet 4 and the lower core cover side 12 (see also FIG.2).

The wetness indicator 29 may form a strip which is generally straightand parallel with the longitudinal axis y1 (see also FIG. 1).Furthermore, the wetness indicator 29 may extend generally symmetricallyin the front portion 6 along said longitudinal axis y1.

The wetness indicator 29 may have a length l4 which is within theinterval of 5-35% of the length l of the absorbent core 5. Also, thewetness indicator 29 may have a length l4 which is within the intervalof 5-35% of the length l1′ of the channel sealings 9, 10.

Although FIG. 3 show an absorbent core 5 with one optional wetnessindicator 29, or two optional wetness indicators 29, 30, it should benoted that, the disclosure is not limited to such an arrangement, butmay be implemented also without such wetness indicators 29, 30.

With reference to FIGS. 1 and 4, the sealing arrangement 9, 10, 15, 16may be constituted by a welding pattern 23 produced by means ofultrasonic welding. The welding pattern 23 may comprise welding spots 24which are arranged in the form of a first row 23 a in which the weldingspots 24 are arranged along a first axis 25. Also, a further number ofwelding spots 24 are arranged in the form of a second row 23 b in whichthe welding spots 24 extend along a second axis 26. Furthermore, thefirst axis 25 and the second axis 26 extend in a manner so that theydefine a first angle α1 in relation to each other. In this manner, itcan be ensured that the absorbent core 5 can be manufactured with a highlevel of material strength in both its longitudinal and transversaldirection.

The welding spots 24 may be of generally rectangular or oblong shape.Also, the above-mentioned first angle α1 may be in the interval of45-130°. As shown in FIG. 4, the first angle α1 may be in the magnitudeof 90°.

Also, as shown in FIG. 4, the first axis 25 may define an angle α2 withreference to said longitudinal axis y1 which is within the interval30-60°.

FIGS. 1 and 4 teaches one row 23 c of welding spots in each side seam15, 16 along the crotch portion 8, and three rows 23 c, 23 d, 23 e ofwelding spots in each side seam 15, 16 along the front portion 6 and theback portion 7, respectively. Also, each side seam 15, 16 may define athird side seam width and a fourth side seam width along the frontportion 6 and back portion 7, respectively.

As shown in FIGS. 4 and 5, the width w2 of the first row 23 a and thesecond row 23 b may be defined as an “effective” width in the sense thatit is equal to the sum of an effective width w2 a of a welding spot 24in the first row 23 a and an effective width w2 b of a welding spot 24in the second row 23 b. Each “effective width” can be defined as thelength of a welding spot 24 in a transverse direction of the article 1,as indicated in FIG. 5. Similarly, the effective width w4 c and w6 c,respectively, of the third row 23 c of welding spots 24 is also shown inFIG. 5. The effective width of the third row 23 c in the crotch portion8 is the length w4 c of a welding spot 24 in said transverse direction,as indicated in FIG. 5. Also, the effective width of the side seam 16outside the crotch portion 8 (as also indicated in FIG. 1, i.e., thecombined effective width of the three rows 23 c, 23 d, 23 e forming theside seam 16, is the sum of the lengths w6 d, w6 c, w6 e in saidtransverse direction, as shown in FIG. 5.

The sum of the effective channel sealing widths w1, w2 and the first andsecond side seam widths w3, w4, w5, w6 in a transversal direction of thearticle 1 may be generally constant along the longitudinal length of thecore 5. This is particularly advantageous in a manufacturing processinvolving ultrasonic welding of the channels sealings 9, 10 and the sideseams 15, 16, since the manufacturing process can be arranged so that agenerally constant energy is required as the ultrasonic welding of thechannels sealings 9, 10 and side seams 15, 16 is produced along thelongitudinal direction of the core 5.

A method for manufacturing an absorbent article 1 will now be described.Firstly, the absorbent core 5 is formed by an absorbent component 5 a, 5b, 5 c and enclosing said absorbent component 5 a, 5 b, 5 c between theupper core cover side 11 and the lower core cover side 12. Next, thesealing arrangement, i.e., the channel sealings 9, 10 and optionally theside seams 15, 16, are formed in a manner so that they join the uppercore cover layer 11 and the lower core cover layer 12. As describedabove, the sealing arrangement 9, 10, 15, 16 may be formed by ultrasonicwelding.

Consequently, the absorbent core 5 may be formed with an absorbentcomponent 5 a, 5 b, 5 c enclosed by a core cover 11, 12 and the sealingarrangement 9, 10, 15, 16 comprising the two channel sealings 9, 10 andoptionally the side seams 14, 15. The upper core cover side 11 and thelower core cover side 12 are joined to define said sealing arrangement9, 10, 15, 16.

The above-mentioned forming step furthermore comprises forming therecess 27 in the front portion 6 of the core 5, wherein the recess 27defines a depth c extending from a front edge 28 of the 5 and into saidfront portion 6. The forming step also comprises forming the core 5 sothat a distance l2 ′ is defined between said front edge 28 of the core 5and a front edge 20 of each channel sealing 9, 10, wherein the ratio ofsaid depth c and said distance l2′ is within the interval 0.05-0.8, suchas 0.15-0.4.

The absorbent core 5 and the sealing arrangement 9, 10, 14, 15 may beformed in a manner so that the centre segment 5 a is formed between thechannel sealings 9, 10 and the two side segments 5 b, 5 c are formedoutside each channel sealing 9, 10. More precisely, the centre segment 5a may have a first width a1 and each side segment 5 b, 5 c may have asecond width a2. Also, the core 5 may be formed with a third width b1between the channel sealings 9, 10 and a fourth width b2 between achannel sealing 9, 10 and a side seam 15, 16.

The article 1 (see FIG. 1) is formed by sandwiching the absorbent core 5between the liquid-permeable topsheet 3 and the liquid-impermeablebacksheet 4. The article 1 defines the longitudinal axis yl and thetransversal axis x1 as described above. Also, the article 1 defines afront portion 6, a back portion 7 and a crotch portion 8. Furthermore,the channel sealings 9, 10 are positioned in the crotch portion 8, i.e.,the length l1′ of each channel sealing 9, 10 (see FIG. 3) may correspondto the extension l1 of the crotch portion 8.

The absorbent component 5 may be formed so that the total amount ofabsorbent material of the centre segment 5 a is generally equal to, orgreater than, the total amount of absorbent material in each one of theside segments 5 b, 5 c. Furthermore, the manufacture method may beconfigured so that the absorbent core 5 is formed so that that the ratioof the first width a1 and the third width b1 is greater than the ratioof the second width a2 and the fourth width b2. This corresponds to thedescription above with reference to FIGS. 1 and 2.

The disclosure may be varied within the scope of the appended claims.For example, the materials and dimensions used for the different layersforming the absorbent article 1 may be varied, as indicated above. Theabsorbent article may further include leg elastics, standing gathers,crotch and waist elastics, side panels, fastening systems etc. as knownto the skilled man in the art and depending of the type of absorbentarticle intended.

The invention claimed is:
 1. An absorbent article comprising: anabsorbent core sandwiched between a topsheet and a backsheet, saidarticle being arranged along a longitudinal axis and a transversal axisextending in a perpendicular direction in relation to the longitudinalaxis and said article defining a front portion, a back portion and acrotch portion, wherein said absorbent core comprises an absorbentcomponent enclosed by a core cover comprising an upper side and a lowerside and the core is formed with a sealing arrangement for joining saidupper and lower sides comprising two channel sealings extending alongsaid longitudinal axis in said crotch portion and defining a firstchannel sealing width and a second channel sealing width, respectively;wherein the front portion of the core is formed with a recess defining adepth extending from a front edge of the core and into said frontportion and a distance is defined between said front edge of the coreand a front edge of each channel sealing, wherein the ratio of saiddepth and said distance is within an interval of 0.05-0.8; and wherein adistance between the channel sealings in a transversal direction of thearticle is less than a maximum width of said recess.
 2. The absorbentarticle according to claim 1, wherein said recess is formed in theabsorbent component.
 3. The absorbent article according to claim 1,wherein said recess is formed in the core cover and the absorbentcomponent.
 4. The absorbent article according to claim 1, wherein saidrecess is shaped generally as a semi-circle, a U-shape, a V-shape or inthe form of a rectangle extending into the front portion.
 5. Theabsorbent article according to claim 1, wherein a distance between saidfront edge of the core and the front edge of each channel sealing iswithin an interval of 50-180 mm.
 6. The absorbent article according toclaim 1, wherein the depth of the recess is within an interval of 10-40mm.
 7. The absorbent article according to claim 1, wherein said corecomprises at least one wetness indicator having a longitudinal extensionand being positioned generally only in said front portion, or only insaid back portion, or in both the front portion and the back portion. 8.The absorbent article according to claim 7, wherein said wetnessindicator is arranged so that the wetness indicator does not extend intosaid crotch portion.
 9. The absorbent article according to claim 7,wherein said wetness indicator is arranged so that the wetness indicatordoes not extend between said channel sealings.
 10. The absorbent articleaccording to claim 1, wherein said absorbent core is generallyrectangular.
 11. The absorbent article according to claim 1, whereinsaid channel sealings are generally parallel to said longitudinal axis.12. The absorbent article according to claim 1, wherein said channelsealings are positioned within two corresponding channels whichconstitute sections of the absorbent core which are generally free fromabsorbent material.
 13. The absorbent article according to claim 1,wherein the channel sealings are formed by a thermo- and/or mechanicalwelding pattern.
 14. The absorbent article according to claim 13,wherein the welding pattern comprises a plurality of welding spotsarranged in the form of a first row in which the welding spots extendalong a first axis and a second row in which the welding spots extendalong a second axis, said first axis and second axis defining a firstangle in relation to each other.
 15. The absorbent article according toclaim 14, wherein said first angle is 45-130°.
 16. The absorbent articleaccording to claim 14, wherein said first axis defines a second anglewith reference to said longitudinal axis which is within an interval of30-60°.
 17. The absorbent article according to claim 1, wherein a centresegment having a first width is defined in the absorbent componentbetween the channel sealings and two side segments each having a secondwidth are defined in the absorbent component outside each channelsealing.
 18. An absorbent core for an absorbent article, said absorbentcore comprising an absorbent component enclosed by a core covercomprising an upper and a lower side and a sealing arrangement forjoining said upper and lower core cover sides, said sealing arrangementcomprising two channel sealings extending along a longitudinal axis andin said crotch portion and defining a first channel sealing width and asecond channel sealing width, respectively; wherein the core comprises afront portion which is formed with a recess defining a depth extendingfrom a front edge of the core and into said front portion and a distanceis defined between said front edge of the core and a front edge of eachchannel sealing, wherein the ratio of said depth and said distance iswithin an interval of 0.05-0.8, wherein a distance between the channelsealings in a transversal direction of the article is less than amaximum width of said recess.
 19. A method for manufacturing anabsorbent article, the article comprising a longitudinal axis and atransversal axis extending in a perpendicular direction in relation tothe longitudinal axis and said article defining a front portion, a backportion and a crotch portion, comprising: forming an absorbent core withan absorbent component and enclosing said absorbent component in a corecover comprising an upper and a lower side; providing two channelsealings in the crotch portion, joining said upper and lower core coversides; and sandwiching said absorbent core between a liquid-permeabletopsheet and a liquid-impermeable backsheet; wherein said forming stepfurthermore comprises: forming a recess in a front portion of the core,said recess defining a depth extending from a front edge of the core andinto said front portion; and forming the core so that a distance isdefined between said front edge of the core and a front edge of eachchannel sealing, wherein the ratio of said depth and said distance iswithin an interval of 0.05-0.8, wherein a distance between the channelsealings in a transversal direction of the article is less than amaximum width of said recess.